September Weather in Santee, United States

Last updated: June 24, 2025

In September, the average temperature in Santee, United States hovers around 25°C (78°F), with extremes ranging from a refreshing 12°C (53°F) to a sweltering 37°C (98°F). Visitors can expect 116 mm (4.6 in) of precipitation over 8 days, while the air remains consistently humid with an average of 83% humidity. Embrace the warmth, but don’t forget your umbrella!

September Temperature in Santee

In September in Santee, the average temperature is 25°C (78°F). Maximums can reach 37°C (98°F), and minimums can be as low as 12°C (53°F). It's a perfect time to enjoy outdoor activities while being prepared for varying temperatures.

September Weather in Santee: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Santee, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Santee, September typically has an average temperature of 25°C (78°F), with highs reaching up to 37°C (98°F) and lows dropping to around 12°C (53°F).

Data source: Temperature data for Santee generated using information from the Copernicus Climate Change Service.

September Precipitation in Santee

In Santee in September, the total precipitation amount is 116 mm (4.6 in) recorded over a span of 8 days.

September Precipitation Trends in Santee

The chart displays monthly precipitation patterns in Santee, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Santee, September typically receives around 116 mm (4.6 inches) of precipitation spread over approximately 8 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

September Humidity in Santee

In Santee in September, humidity is 83%. With an average temperature of 25°C (78°F), this humidity feels like stepping into a warm, damp embrace, making travel sticky and exhausting, as each movement can leave you drenched in sweat.

September Average Humidity in Santee

This chart illustrates the average monthly humidity levels in Santee, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Santee is approximately 83%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Santee

In Santee in September, the maximum UV index is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, you can check the Hourly UV Index in Santee.

Maximum UV Index Levels in Santee for September

The chart shows the monthly maximum UV Index (UVI) for Santee in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Santee typically reaches 9, which falls under the very high exposure category.

Data source: Santee September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How September Weather in Santee Compares to Other Months

Weather in Santee varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Santee, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Santee, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	10°C (50°F)	75 mm (2.9 inches)	86%	moderate
February Weather	13°C (55°F)	95 mm (3.7 inches)	81%	high
March Weather	15°C (59°F)	76 mm (3.0 inches)	81%	very high
April Weather	19°C (66°F)	114 mm (4.5 inches)	79%	very high
May Weather	23°C (74°F)	92 mm (3.6 inches)	75%	extreme
June Weather	26°C (79°F)	114 mm (4.5 inches)	75%	extreme
July Weather	28°C (82°F)	158 mm (6.2 inches)	80%	extreme
August Weather	27°C (81°F)	136 mm (5.3 inches)	81%	extreme
September Weather	25°C (78°F)	116 mm (4.6 inches)	83%	very high
October Weather	21°C (70°F)	61 mm (2.4 inches)	78%	very high
November Weather	13°C (56°F)	66 mm (2.6 inches)	85%	high
December Weather	11°C (52°F)	137 mm (5.4 inches)	87%	moderate